Granular detergent composition containing enzymes and environmental control components

ABSTRACT

GRANULAR DETERGENT COMPOSITION CONTAINING ENZYMES AND ENVIRONMENTAL CONTROL COMPONENTS WHEREIN THE ENVIRONMENTAL CONTROL COMPONENTS ARE SELECTED FROM THE GROUP CONSISTING OF SODIUM PERBORATE TRIHYDRATE, ANHYDROUS TRISODIUM PHOSPHATE, ANHYDROUS CALCIUM SULFATE AND MIXING THEREOF; AND SOLUBLE OR DISPERSIBLE PROTEINS HAVING A MOLECULAR WEIGHT OF BETWEEN ABOUT 5,000 AND 1,000,000 IN AN EFFECTIVE AMOUNT TO STABILIZE THE ENZYMES IN THE GRANULAR DETERGENT COMPOSITION IN COMBINATION WITH A COMPONENT SELECTED FROM THE GROUP CONSISTING OF SODIUM PERBORATE TRIHYDRATE, ANHYDROUS TRISODIUM PHOSPHATE, ANHYDROUS CALCIUM SULFATE AND MIXTURES THEREOF.

J n- 26,1971 JEAN-PIERRE D. EYMERY ET AL AND ENVIRONMENTAL CONTROLCOMPONENTS Filed Nov. 29, 1967 50 RELATIVE HUMIDITY GRANULAR DETERGENTCOMPOSITION CONTAINING ENZYMES 5 0 O O O O O O 0 mm 9 8 7 6 5 4.3

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ATTORNEYS United States Patent 01 3,558,498. Patented Jan. 26, 19713,558,498 GRANULAR DETERGENT COMPOSITION CON- TAINING ENZYMES ANDENVIRONMENTAL CONTROL COMPONENTS Jean-Pierre D. B. Eymery and Harold H.Beyer, Springfield Township, Hamilton County, Ohio, assignors to TheProcter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio FiledNov. 29, 1967, Ser. No. 686,403 Int. Cl. C11d 3/04 US. Cl. 252-135 8Claims ABSTRACT OF THE DISCLOSURE Granular detergent compositioncontaining enzymes and environmental control components wherein theenvironmental control components are selected from the group consistingof sodium perborate trihydrate, anhydrous trisodium phosphate,anhydrous, calcium sulfate and mixture thereof; and soluble ordispersible proteins having a molecular weight of between about 5,000and 1,000,000 in an effective amount to stabilize the enzymes in thegranular detergent composition in combination with a component selectedfrom the group consisting of sodium perborate trihydrate, anhydroustrisodium phosphate, anhydrous calcium sulfate and mixtures thereof.

FIELD OF THE INVENTION The present invention relates to a granulardetergent composition containing enzymes and environmental controlcomponents. The environmental control components utilized herein inhibitoxidation and/or autolysis of enzymes by controlling the relativehumidity in the packaged granular, enzyme-containing detergentcomposition and, in one embodiment, by complexing the enzymes withproteins in conjunction with controlling the relative humidity in thepackaged granular detergent composition.

HISTORY OF THE INVENTION The use of enzymes in admixture with detergentcompositions is quite old. See Ferlinghusen, U.S. Pat. 1,882,279 (Oct.11, 1932). Enzymes employed in this manner de compose or alter thecomposition of ordinary soil and render the soil particles more easilyremovable with the use of conventional washing products.

However, when enzymes are stored for long periods of time in such adetergent environment, especially in hot and humid climates, a largeportion of the enzymes are degraded and/or deactivated. Enzymes used inconjunction with most oxygen bleaches are also easily degraded and/ordeactivated when stored for long periods. These problems have beenrecognized by at least one enzyme manufacturer. See Alcalase, anindustrial bulletin published by Novo Industri, A/S, Copenhagen,Denmark.

Successful methods of increasing enzyme stability at ordinary storagetemperatures and humidities are documented in the copending US. patentapplications of McCarty, Enzyme-Containing Detergent Compositions and aProcess for Conglutination of Enzymes and Detergent Compositions, Ser.No. 635,293, filed Apr. 12, 1967 (hereinafter cited as McCarty), andRoald and De Oude, Granular Enzyme-Containing Laundry Compositions, Ser.No. 630,199, filed Apr. 12, 1967 (hereinafter cited as Roald et al.),now US. Pat. 3,451,935.

SUMMARY OF THE INVENTION The primary object of this invention is toprovide an enzyme-containing granular detergent composition wherein theenzymes are stable during long storage periods and particularly whereinthe enzymes are stable during long storage periods at high temperaturesand high humidities.

The primary object and other objects which will become apparent fromreading the specification are obtained with a granular,enzyme-containing detergent composition comprising, by weight of thedetergent composition:

(1) from about 60% to about 98% of detergent granules comprisingpolymeric builder salts and organic detergents, the ratio of polymericbuilder salts to organic detergents in the detergent composition of thisinvention ranging from about 30:1 to about 1:4;

(2) from about 0.001% to about 1.0% of enzymes which are active in thepH range of from about 5.0 to about 11.0 and in the temperature range offrom about 50 F. to about 170 F.; and

(3) environmental control components selected from the group consistingof, by weight of the detergent composition:

(a) from about 5% to about 30% of sodium perborate trihydrate;

(b) from about 4% to about 15% of components which hydrate at belowabout 50% relative huimdity selected from the group consisting ofanhydrous trisodium phosphate, anhydrous calcium sulfate, and mixturesthereof;

(c) mixtures of from about 5% to about 30% of component (a) and fromabout 4% to about 15 of components (b); and

(d) proteins in an effective amount to stabilize the enzymes in thegranular detergent composition, said proteins having a molecular Weightof between about 5,000 and 1,000,000 and being soluble or dispersible inwater, in combination with components selected from the group consistingof from about 5% to about 30% of component (a) hereinbefore described;from about 4% to about 15% of components (b) .hereinbefore described;and mixtures of from about 5% to about 30% of component (a) and fromabout 4% to about 15 of components (b).

This invention is particularly designed to increase the storage life orstability of enzymes in granular, enzymecontaining, detergentcompositions which are stored and/or used in hot, humid climates.

THE DRAWING The drawing illustrates the effect of relative humidity onenzyme stability when granular, enzyme-containing detergent compositionsare stored for nine days at F. and at F. It is apparent from thesecurves that the enzymes are quite stable at relative humidities of about50% and below. As the relative humidity is raised, however, degradationand/ or deactivation of the enzymes increases. The detergent compositionutilized in experiments to obtain this graphic representation wascomprised of, in parts by weight, 24 parts sodium alkyl benzenesulfonate derived from tetrapropylene, 24 parts sodium tripolyphosphate,5.4 parts sodium silicate (SiO :Na O ratio of 2:1), 24.3 parts sodiumsulfate, 2.5 parts sodium toluene sulfonate, 10 parts sodium perboratetetrahydrate, 9.1 parts water, and 0.7 part Alcalase. The initial enzymeactivity reading of may represent minor analytical error or may indicatea minor error in the initial preparation of the enzyme-containinggranular detergent composition.

DETAILS AND DESCRIPTION OF THE INVENTION The granular, enzyme-containingdetergent composition of this invention is comprised of three majoringredients: the detergent granules, the enzymes and the environmentalcontrol components. These ingredients are described hereinafter. Allparts, percentages and ratios set forth in the specification, theexamples and the appended claims are by weight unless otherwiseindicated.

DETERGENT GRANULES The bulk of the granular, enzyme-containing detergentcomposition of this invention, i.e., from about 60% to about 98%,preferably from 70% to 95%, is made up of ordinary detergent granulescomprising polymeric builder salts and organic detergents. The polymericbuilder salts are selected from the group consisting of polyphosphate,polyphosphonate, polyacetate and polycarboxylate builder salts ormixtures thereof. The polyphosphate builder salts are exemplified by thesodium and potassium salts of tripolyphosphoric acid.

Polyphosphonates are also valuable builders in terms of the presentinvention including specifically sodium and potassium salts of methylenediphosphonic acid, sodium and potassium salts of ethylene diphosphonicacid, sodium and potassium salts of ethane-l-hydroxy-1,1-diphosphonicacid and sodium and potassium salts of ethane- 1,1,2-triphosphonic acid.Other examples include the water soluble [sodium, potassium, ammoniumand substituted ammonium (substituted ammonium, as used herein, includesmono, di-, and triethanol ammonium cations)] salts ofethane-Z-carboxy-l,l-diphosphonic acid, hydroxymethanediphosphonic acid,carbonyldiphosplionic acid, ethane-l-hydroxy-l,1,2-triphosphonic acid,ethane-2- hydroxy-l,1,2-triphosphonic acid, propane-1,l,3,3-tetraphosphonic acid, propane-1,123 -tetraphosphonic acid, andpropane-1,2,2,3-tetraphosphonic acid.

Examples of the above polyphosphonic compounds are disclosed in US.Pats. 3,159,581 and 3,213,030 and US. Pat. applications, Ser. No.266,055, filed Mar. 18, 1963, and now US. Pat. 3,422,021; Ser. No.368,419, now abandoned, filed May 18, 1964; Ser. No. 517,073, filed Dec.28, 1965, and now US. Pat. 3,422,137; Ser. No. 507,662, filed Nov. 15,1965, and now US. Pat. 3,400,176; and Ser. No. 489,637, filed Sept. 23,1965, and now US. Pat. 3,400,148.

The polyacetate builder salts suitable for use herein include thesodium, potassium, lithium, ammonium and substituted ammonium salts ofthe following acids: ethylenediaminetetraacetic acid, N- (Z-hydroxyethyl-etl1ylenediaminetriacetic acid, N (2-hydroxyethyl)-nitrilodiaceticacid, diethylenetriaminepentaacetic acid,1,2-diaminocyclohexanetetraacetic acid and nitrilotriacetic acid. Thetrisodium salts of the above acids are generally and preferably utilizedherein.

The polycarboxylate builder salts suitable for use herein consist ofwater-soluble salts of polymeric aliphatic polycarboxylic acids selectedfrom the group consisting of:

(a) Water-soluble salts of homopolymers of aliphatic polycarboxylicacids having the following empirical formula:

I Y COOH wherein X, Y and Z are each selected from the group consistingof hydrogen, methyl, carboxyl and carboxymethyl, at least one of X, Yand Z being selected from the group consisting of carboxyl andcarboxymethyl, provided that X and Y can be carboxy-methyl only when Zis selected from carboxyl and carboxymethyl, wherein only one of X, Yand Z can be methyl, and wherein n is a Whole integer having a valuewithin a range, the lower limit of which is three and the upper limit ofwhich is determined by the solubility characteristics in an aqueoussystem;

(b) Water-soluble salts of copolymers of at least two of the monomericspecies having the empirical formula described in (a); and

(c) Water-soluble salts of copolymers of a member selected from thegroup of alkylenes and monocarboxylic acids with the aliphaticpolycarboxylic compounds described in (a), said copolymers having thegeneral formula:

r r t 5 7 11 R 1-... Y C0011 wherein R is selected from the groupconsisting of hydrogen, methyl, carboxyl, carboxymethyl andcarboxyethyl; wherein only one R can be methyl; wherein m is at leastmole percent of the copolymer; wherein X, Y and Z are each selected fromthe group consisting of hydrogen, methyl, carboxyl and carboxymethyl; atleast one of X, Y and Z being selected from the group of carboxyl andcarboxymethyl provided that X and Y can be carboxymethyl only when Z isselected from the group of carboxyl and carboxymethyl, wherein only oneof X, Y and Z can be methyl and wherein n is a whole integer Within arange, the lower limit of which is three and the upper limit of which isdetermined primarily by the solubility characteristics in an aqueoussystem; said polyelectrolyte builder material having a minimum molecularWeight of 350 calculated as the acid form and an equivalent weight ofabout to about 80, calculated as the acid form, (e.g., polymers ofitaconic acid, aconitic acid; maleic acid; mesaconic acid; fumaric acid;methylene malonic acid; and citraconic acid and copolymers withthemselves and other compatible monomers such as ethylene), Thespolycarboxylate builder salts are more specifically described in US.Pat. 3,308,067, issued Mar. 7, 1967 to Francis L. Diehl entitledPolyelectrolyte Builders and Detergent Compositions.

Mixtures of the above-described polymeric builder salts can be utilizedto advantage in this invention.

The organic detergents suitable for use herein include soap, anionicsynthetic detergents, nonionic synthetic detergents, zwitterionicsynthetic detergents and ampholytic synthetic detergents and mixturesthereof. These organic detergents are described in detail in US. Pat.3,351,558 issued Nov. 7, 1967 to Roger Earl Zimmerer entitled DetergentComposition Containing Organic Phosphonate Corrosion Inhibitors,starting at column 6, line 59 and ending at column 9, line 74.

It is preferred that these detergent granules, when utilized in thisinvention, be dried to a total moisture content of less than 8%.

The detergent granules utilized in this invention are generallycomprised of organic detergents and polymeric builder salts; however,detergent granules comprising only organic detergents or only polymericbuilder salts can be utilized herein specialized applications, e.g.,detergent granules comprising only polymeric builder salts can beutilized as enzyme carriers in this invention. The weight ratio oforganic detergents to polymeric builder salts in the detergentcomposition of this invention ranges from about 4:1 to 1:30, preferablyfrom 1:1 to 1:15. The granules generally range in size from aboutthrough a Tyler Standard 6 mesh screen (3:33 mm.) to about 100% on aTyler Standard 200 mesh screen (0.074 mm.) Segregation of granules inthe detergent composition is minimized when the particle sizes rangefrom about 100% through a Tyler Standard 12 mesh screen (1.40 mm.) toabout 100% on 21 Tyler Standard 100 mesh screen (0.15 mm.) and,therefore, these particle sizes are preferred. The bulk density of thedetergent granules, in order to inhibit segregation, generally rangesfrom about 0.2 gms./cc. to about 0.8 gms./cc.

The detergent granules utilized in this invention can be formed by avariety of well-known methods. For example, the various detergentingredients can be incorporated into a detergent slurry and spray dried.The detergent granules can also be obtained by agglomerating powders ofthe various detergent ingredients.

ENZYMES Enzymes suitable for use in this invention which degrade oralter one or more types of soil are large in number and can be groupedinto five large classes on the basis of the reactions which they performin such degradation or alteration. These broad classifications ofenzymes are described with particularity in McCarty, at pages 5 through15 (these pages are specifically incorporated by reference herein).These enzymes, to be useful herein, must be relatively stable indetergent solutions and must be instrumental in removing soil and/orstains from fabrics. Therefore, these enzymes should be active at a pHranging from about 5 to about 11 and at temperatures ranging from about50 F. to 170 F. As used herein, enzyme activity refers to the ability ofan enzyme to perform the desired function of soil attack and enzymestability refers to the ability of an enzyme to remain in an activestate.

The enzymes suitable for use herein should also be relatively stablewhen stored in the packaged granular detergent composition of thisinvention. Degradation and/or deactivation of the enzymes can beinhibited or minimized by incorporating the enzymes with the detergentgranules in accordance with the teachings of copending United Statespatent applications, Roald et al. and McCarty. The enzymes can also bedry-mixed with the detergent components.

Among the many enzyme classes and examples of enzymes discussed inMcCarty, the proteases and a-amylases are preferred for use in thisinvention.

All of the u-amylases show optimum activity in the acid range and areparticularly well suited for breaking down starch molecules as theyattack the a glycosidic linkages in starch. The remaining shorter chainsare easily removed with aqueous solutions of detergents. The a-amylasesmay be obtained from animal sources, cereal grains, bacterial or fungalsources. a-Amylase compositions which are commercially available can beutilized herein. Specific examples of these compositions includeWallerstein bacterial a-amylase; Miles a-amylase; Nono a-amylase;Diastatic H-39; Midwest Biochemical a-amylase.

The proteases are generally classified as alkaline proteases, neutralproteases and acid proteases. These classifications indicate the pHrange in which optimum enzyme activity is obtained. The alkalineproteases are preferred for use herein. For a more complete discussionif the alkaline, neutral and acid proteases, see McCarty, StabilizedAqueous Enzyme Preparation, Ser. No. 683,- 196, filed Nov. 15, 1967, atpage 6.

The proteases catalyze the hydrolysis of the peptide linkage ofproteins, polypeptides and related compounds. Free amino and carboxylgroups are thus obtained and the long chain protein structure is reducedto several shorter chains which can be removed from fabrics withordinary detergent compounds.

Specific examples of proteases suitable for use in this invention arepepsin, trypsin, chymotrypsin, collagenase, keratinase, elastase,subtilisin, BPN' papain, ficin, bromelin, carboxy peptidase, aminopeptidase, aspergillopeptidase A and aspergillopeptidase B and thoseproteolytic enzymes isolated from streptomyces species. Preferredpoteases are subtilisin, BPN, and those proteases isolated fromstreptomyces species.

Protease composition commercially available can be utilized in thisinvention. The commercial enzyme compositions containing proteases aregenerally sold in a powdered form and are comprised of active enzymes incombination with relatively inert ingredients such as sodium or calciumsulfate or sodium chloride. Specific examples of these commercialcompositions and the manufacture thereof include: Alcalase; Maxatase;Protease B-4000 and Sandoz AP and AP 2100; CRD-Protease (includes someuamylase); Pronase-E, Pronase-P;

Pronase-AS and Pronase-AF; Bioprase (includes some and proteolyticenzyme 7XB; Pl1 concentrate, Rhozyme PF, Rhozyme J-25; and Wallerstein627-P.

CRD Protease, Pronase-P, Pronase-AS, Pronase-AF and Alcalase are morespecifically described in McCarty at pages 12-13. (These pages arespecifically incorporated by reference herein.)

Large variations in the amount of enzymes in the detergent compositionof this invention are contemplated. The detergent composition cancontain from about 0.001% to about 1% of enzymes by weight of thedetergent composition of this invention. For best results, the detergentcomposition should contain from about 0.01% to about 0.5% enzymes byweight. When one of the preferred enzyme compositions is utilized inthis in vention, the granular detergent composition preferably containsfrom about 0.1% to about 4% of the enzyme composition as it is sold incommercial form, e.g., from about 2% to about active enzymes. Theremainder of the enzyme composition is generally comprised of inertingredients as discussed hereinbefore.

ENVIRONMENTAL CONTROL COMPONENTS The environmental control components ofthis invention are beneficial additives to granular, enzyme-containing,detergent compositions because they inhibit or im pede degradationand/or deactivation of the enzymes. Degradation as used herein refers toa breakdown or destruction of the protein structure of the enzymes whiledeactivation refers to alterations. of the active sites of enzymes whichchange or inhibit normal enzyme activity. Degradation and/ordeactivation of enzymes in a granular detergent composition is inhibitedor impeded by maintaining the relative humidity in the packageddetergent composition as low as possible, preferably below about 50%(see the drawing). This stabilization effect (prevention of degradationand/or deactivation) is further enhanced by complexing the enzymes witha protein which is soluble or dispersible in water to impede autolysisand/or oxidation.

The environmental control components suitable for use herein whichinhibit or impede degradation and/or deactivation of enzymes in agranular detergent com position are selected from the group consistingof, by weight of the granular detergent composition:

(a) From about 5% to about 30% of sodium perborate trihydrate;

(b) From about 4% to about 15% of components which hydrate at belowabout 50% relative humidity selected from the group consisting ofanhydrous trisodium phosphate, anhydrous calcium sulfate and mixturesthereof;

(c) Mixtures of from about 5% to about 30% of component (a) and fromabout 4% to about 15% of components (b); and

(d) Proteins in an effective amount to stabilize the enzymes in thegranular detergent composition, said proteins having a molecular weightof between about 5,000 and 1,000,000 and being soluble or dispersible inwater, in combination with components selected from the group consistingof from about 5% to about 30% of said component (a) hereinbeforedescribed; from about 4% to about 15% of said components (b)hereinbefore described; and mixtures of from about 5% to about 30% ofcomponent (a) and from about 4% to about 15% of components (b).

The drawing illustrates that degradation and/or deactivation of enzymesin a packaged granular detergent composition is strongly influenced. bythe relative humidity. The influence of relative humidity on enzymestability is most apparent at relatively high storage temperatures,e.g., 75 F. to F. At lower storage temperatures, the detrimental effectsof relative humidity on enzymes are not as readily apparent and do notpresent serious storage problems.

An important function of the environmental control components of thisinvention is the control of the relative humidity in the packagedgranular detergent composition. This is accomplished by utilizingthermodynamically stable components and components which hydrate atrelative humidities below about 50%. These components control therelative humidity of the enzyme environment (the packaged granulardetergent composition) and promote enzyme stability. When very harshstorage conditions, e.g., 90 F. and 80% relative humidity, areencountered, the relative humidity in the packaged granular detergentcomposition of this invention may rise considerably, especially whereprotective packaging is not utilized. Even though the relative humidityof the packaged granular detergent composition of this invention mayrise above the optimum of about 50% relative humidity under harshstorage conditions, the relative humidity of the packaged composition ofthis invention is still considerably below the relative humidity of asimilar packaged granular detergent composition which does not containthe environmental control components of this invention. The packagedgranular detergent composition of this invention thus provides anenvironment in which degradation and/or deactivation of enzymes isdecreased and enzyme stability is promoted.

To obtain optimum whitening and stain removal without the harsh effectsof hypochlorite bleaches, oxygen bleaches are generally added togranular detergent compositions. The most commonly used oxygen bleachesare sodium perborate monohydrate and sodium perborate tetrahydrate.Unfortunately, the addition of these sodium perborate hydrate species toenzyme-containing detergent compositions, especially when thesedetergent compositions are stored at high temperatures, can causedegradation and/or deactivation of the enzymes. Sodium perboratetetrahydrate is thermodynamically unstable and, when subjected totemperatures of more than about 90 F., rapidly loses water of hydrationto the atmosphere. Release of water in a packaged, granular,enzyme-containing detergent composition significantly increases therelative humidity in the package and causes degradation and/ordeactivation of the enzymes. Sodium perborate monohydrate, when utilizedin enzyme-containing detergent compositions, also causes deactivationand/ or degradation of enzymes. It is believed that this hydrate speciescompetes vigorously for available water and forms the tetrahydrate. Whensubjected to heat, the tetrahydrate breaks down with thebefore-mentioned consequences. The mechanism of degradation and/ordeactivation of the enzymes is not known with certainty although it isbelieved that the enzymes are degraded through a combination of enzymeautolysis (self-destruction) and oxidation. The enzymes are oxidized insuch a manner that the function of the active enzyme sites isdetrimentally altered.

According to this invention, this beneficial oxygen bleaching isobtained without the detrimental increase in relative humidity andconcomitant enzyme degradation and/or deactivation by utilizing fromabout to about 30% of thermodynamically stable soduim perboratetrihydrate instead of the detrimental sodium perborate hydrate speciesabove described. Sodium perborate trihydrate is not readily convertibleto the thermodynamically unstable tetrahydrate form and does not releaseits water of hydration until temperatures of about 130 F. are attained.This hydrate form is compatible with ordinary detergent ingredients and,additionally does not as readily alter the environment of the enzymesand, thus, cause degradation and/or deactivation of the enzymes utilizedin the granular detergent composition of this invention.

Sodium perborate trihydrate is generally manufactured in afinely-divided powder form. To prevent segregation of the sodiumperborate trihydrate particles in the granular, enzyme-containingdetergent composition of this invention, sodium perborate trihydrateagglomerates can be formed. The sodium perborate trihydrate particlescan be formed into agglomerates of approximately the same size anddensity as the detergent granules by coating those particles with anormally solid, liquified nonionic detergent (for examples of suitablenonionic detergents, see McCarty at pages 17 through 21; these pages arespecifically incorporated by reference herein); glue (for example,dextrin), or an aqueous solution of sodium silicate and agglomeratingthe particles in a cement mixer, pan agglomerator or similar equipment.

The sodium perborate trihydrate particles, or preferably agglomerates,are generally dry-mixed into the detergent composition of thisinvention. These particles or agglomerates can be incorporated into thedetergent granules but such incorporation is not generally practicedbecause of the difficult processing problems involved.

When sodium perborate trihydrate is utilized in the granular,enzyme-containing detergent composiiion of this invention, it ispreferred that other oxygen bleaches not be utilized in conjunctiontherewith.

According to this invention, the relative humidity in the packageddetergent composition can be controlled by the addition of from about 4%to about 15%, preferably from 7% to 15%, of components which hydrate atrelative humidities below about These components are selected from thegroup consisting of anhydrous trisodium phosphate, anhydrous calciumsulfate and mixtures thereof. The preferred component for use herein isanhydrous trisodium phosphate.

These components are most preferably dry-mixed into the detergentcompositions. They preferably are not an integral portion of thegranules to which enzymes are attached because these components tend todraw moisture to themselves. If these components were an integral partof the granules to which the enzymes were attached, they might also drawmoisture to the enzymes with concomitant degradation and/ ordeactivation of the enzymes.

Combinations of sodium perborate trihydrate and anhydrous trisodiumphosphate, anhydrous calcium sulfate or mixtures thereof can also beused herein. They are utilized in the amounts set forth above, i.e.,from about 5% to about 30% of sodium perborate trihydrate and from 2% to15% of components selected from the group consisting of anhydroustrisodium phosphate, anhydrous calcium phosphate and mixture thereof.The enzyme stabilizing effect is additive.

Proteins having a molecular weight of between about 5,000 and 1,000,000which are soluble or dispersible in water are utilized herein in aneffective amount to stabilize the enzymes in the granular detergentcomposition in combination with the above described sodium perboratetrihydrate and/ or anhydrous trisodium phosphate, anhydrous calciumsulfate or mixtures thereof in the amounts set forth above. Examples ofproteins which are soluble or dispersible in water and suitable for useherein include casein (average molecular weight 50,000 to 200,000),Wilson Protein WSP-X-1000 (a solubilized collagen having an averagemolecular weight of 10,000), Knox gelatin, alpha protein (soy protein),gelation, zein, collagen and albumins such as bovine albumin and eggalbumin. Wilson Protein WSP-X-1000 is especially preferred for useherein. These proteins are preferably utilized herein in a weight ratioof proteins to eznymes of from about 1:1 to about 10: 1.

The proteins utilized herein are generally obtained in a powdered formand this form is preferred for use herein. It is important that theproteins utilized herein be soluble or dispersible in water. Theseproperties, i.e., solubility and dispersibility, facilitate complexingthe enzyme and the protein and inhibit deposition of proteins on fabricsbeing laundered with concomitant yellowing of the fabrics. Aqueoussolutions or dispersions of proteins can also be utilized herein.

While not wishing to be bound by any particular theory, it is believedthat the proteins, as described above, are instrumental in preventingautolysis and/ or oxidation of the enzymes. It is believed thatautolysis and oxidation are prevented by the formation of anenzyme-protein complex. The enzymes, in this complexed form, areprotected from oxidation and are separated from each other therebypreventing autolysis. When this enzyme-protein complex is exposed towater or aqueous detergent solutions, however, the complex is severedand the enzymes can then act on soil clinging to the fabrics beinglaundered. Because this enzyme-protein complex is easily severed oncontact with moisture, the relative humidity in the package should becontrolled, preferably with the use of the hereinbefore describedenvironmental control components.

The protein is preferably incorporated into the detergent composition ofthis invention by mixing the enzymes and the protein with water andspraying this mixture onto a portion of the detergent granules. Thesedetergent granules can be specially formulated to contain primarilypolymeric builder salts or they can have a composition similar to therest of the detergent granules. By utilizing this method, contactbetween the enzymes and the protein is assured and maximum stabilizingof the enzymes is obtained.

The proteins can be mixed with the enzymes by other methods. Theproteins and enzymes can simply be dry mixed into the detergentcomposition or they can be mixed with all of the various ingredients,selected ingredients or a portion thereof of the detergent compositionin the presence of water, liquified nonionic detergents (such as thosedescribed in McCarty at pages 17 through 21) or the like to formagglomerates.

The proteins are utilized in a granular, enzyme-com taining detergentcomposition in combination with sodium perborate trihydrate and/oranhydrous trisodium phosphate, anhydrous calcium sulfate or mixturesthereof. When proteins are utilized in combination with thesecomponents, enzyme stabilization is enhanced.

To maintain optimum environmental conditions and to obtain maximumenzyme stability in the granular enzyme-containing detergent compositionof this invention, a moisture resistant package should be utilized. Thepackage is important, especially when the temperature and humidity arehigh, in preventing large amounts of moisture which cannot beassimilated by the environmental control components described above fromentering the detergent package from the atmosphere. Examples of packageswhich are preferably utilized in commercial applications of thisinvention are foil Wrapped cartons, asphalt laminated cartons, outer waxlaminated cartons and polyethylene bags. Even when the package is notmoisture resistant, the detergent composition of this invention isstable for a longer period of time than a comparable detergentcomposition which does not contain the environmental control componentshereinbefore described.

EXAMPLES The following examples merely serve to illustrate the inventionin specific detail and when read in conjunction with the foregoingdescription will aid in determining the scope of the present invention.The examples are merely illustrative and are not meant to restrict theinvention.

Example I A mixture of water and Alcalase was sprayed onto anhydroussodium tripolyphosphate in accordance with the method described inExample V of Roald et al. at pages 35 and 36 to obtain an enzyme-carriercomposition comprising 0.5 part Alcalase (6% crystalline enzyme), 5.4parts sodium tripolyphosphate, and 1.1 parts water.

81.0 parts of the detergent granules were mixed with 10 parts of sodiumperborate trihydrate and 7.0 parts or the enzyme-carrier composition toform Composition A.

Control detergent compositions were prepared containing, as replacementsfor sodium perborate trihydrate, sodium perborate tetrahydrate(Composition B) and so dium perborate monohydrate (Composition C). There placements were made on an equal oxygen basis.

Compositions A, B and C were each separated into two equal portions andthese portions were placed in separate sealed glass jars. Portions ofCompositions A, B and C were stored at 90 F. and other portions of thesecompositions Were stored at 110 F. The relative humidity outside theglass jars was about At the beginning of this experiment, the relativehumidity inside the glass jars was about 50%. The relative humidityoutside of the glass jars did not influence this test because the jarswere sealed. The results are summarized in the following table:

1 Percent remaining activity of the enzymes was determined by theAzocoll method. The Azoeoll method is based on the release of awatersoluble dye from a water-insoluble protein dye substrate (Azocoll)by a proteolytic enzyme. The amount of dye released under carefullycontrolled conditions is measured speetrophotometrieally. Enzymaticactivity is calculated from the amount of dye released.

It is evident from the above table that the enzyme activity remainingafter ninety days is substantially greater when sodium perboratetrihydrate is utilized in the above composition than when sodiumperborate monohydrate or sodium perborate tetrahydrate is utilizedtherein. In both storage tests, F. and F., Composition A containing 10%sodium perborate trihydrate retained at least 10% more enzyme activityafter ninety days storage than either Composition B or Composition C. Itis believed that the sodium perborate monohydrate and tetra'hydratespecies caused an increase in the relative humidity in the sealed glassjars with concomitant enzyme degradation and/or deactivation.

Composition A of this example is beneficial in removing stains fromfabrics and for general cleaning and whitening of fabrics. It can alsobe utilized in other washing applications.

Example II Spray-dried detergent granules were prepared com prising thefollowing ingredients:

A mixture of water and Alcalase was sprayed onto anhydrous sodiumtripolyphosphate in accordance with the method described in Example I toobtain an enzymecarrier composition comprising 0.5 part Alcalase (6%crystalline enzyme), 5.4 parts sodium tripolyphosphate, and 1.1 partswater.

81.0 parts of the spray-dried detergent granules were mixed with 10parts of sodium perborate tetrahydrate, 7.0 parts of the enzyme-carriercomposition, and 10 parts of anhydrous trisodium phosphate to formComposition D. Composition E was prepared containing 81.0 parts of thespray-dried detergent granules, 10 parts of sodium perboratetetrahydrate, 7.0 parts of the enzymecarrier composition and parts ofanhydrous trisodium phosphate. A control detergent composition,Composition F was prepared having the same ingredients as Composition Dexcept that the parts anhydrous trisodium phosphate of Composition D wasleft out. Portions of Compositions D, E and F were placed inpolyethylene bags and stored at 90 F. and 80% relative humidity for 63days. The relative humidity in the polyethylene bags at the beginning ofthis experiment was about The results are tabulated in the followingtable:

1 Percent remaining activity of the enzymes was determined by theAzoeoll method. See Example I, Table 1, footnote 1 [or a more completediscussion of the Azocoll method.

Both composition D, containing 10% anhydrous trisodium phosphate, andComposition E, containing 5% anhydrous trisodium phosphate, retainedsignificantly more enzyme activity after storage for 63 days at 90 F.and 83% relative humidity than did Composition P which contained noanhydrous trisodium phosphate. It is believed that the water ofhydration of the sodium perborate tetrahydrate or a portion thereof wasreleased in Compositions D, E and F. In Compositions D and E, thisreleased water of hydration or a portion thereof, was bound as water ofhydration by the trisodium phosphate thereby preventing enzymedegradation and/ or deactivation. It is believed that the water ofhydration which was released in Composition F was responsible for thepoor showing of that composition in comparison with Compositions D andE.

Some enzyme degradation and/0r deactivation was probably also caused byslight amounts of moisture from the high humidity storage area diffusingthrough the polyethylene bags. This moisture, or a portion thereof, wasbound as water of hydration by the trisodium phosphate in Compositions Dand E. In Composition F, this moisture raised the relative humidity withthe abovedescribed results.

As environmental conditions become less conducive to enzyme stability,additional portions of the environmental control components describedherein become useful. As illustrated in Table 2, enzymes in a granulardetergent composition containing 10 parts by weight of anhydroustrisodium phosphate are more stable than enzymes in the granulardetergent composition containing 5 parts by weight of anhydroustrisodium phosphate.

Example III Spray-dried detergent granules are prepared comprising thefollowing ingredients: Ingredient- Parts by weight Sodium alkyl benzenesulfonate derived from tetrapropylene 24.0 Sodium tripolyphosphate 18.6Sodium silicate (SiO :Na O ratio of 2:1) 5.4 Sodium sulfate 24.3

1 2 Ingredient- Parts by weight Sodium toluene sulfonate 2.5

Water 6.2

Total 81.0

A mixture of water, Alcalase and Wilson Protein WSP-X-lOOO protein(partially hydrolyzed and solubilized protein having an averagemolecular weight of about 10,000) is sprayed onto anhydrous sodiumtripolyphosphate in accordance with the method described in Example Ito' obtain an enzyme-carrier composition comprising 0.5 part Alcalase(6% crystalline enzyme), 0.125 part WSP-X-1000 protein and 5.275 partssodium tripolyphosphate and 1.1 parts water.

81 parts of the spray-dried detergent granules are mixed with 7 parts ofthe enzyme-carrier composition and 10 parts sodium perborate trihydrateto form Composition G; 0.125 part casein are utilized in place of theWilson Protein WSP-X-lOOO in Composition G to form Composition H. Thedetergent compositions are packed sepa rately in polyethylene bags andare stored for days at F. and 80% relative humidity. The combination ofprotein and sodium perborate trihydrate has a definite stabilizingeffect on the enzymes.

Example IV Spray-dried detergent granules are prepared comprising thefollowing ingredients:

In gredient Parts by weight Sodium dodecyl benzene sulfonate 10 Sodiumtallow alkyl sulfate 10 Sodium tripolyphosphate 50 Sodium silicate (SiO:Na O ratio of 2:1) 6 Sodium sulfate 16 Water 8 Total Alcalase, WilsonProtein WSP-X-1000 and special enzyme-carrier granules are conglutinatedwith tallow alcohol ethoxylated with 30 moles of ethylene oxide per moleof tallow alcohol (TAE in accordance with the method described inMcCarty in Example I at pages 40 to 42 to obtain an enzyme-carriercomposition comprising 1.0 part Alcalase (6% crystalline enzyme), 0.2part Wilson Protein WSPX1000, 1.0 part tallow alcohol ethoxylated with30 moles of ethylene oxide per mole of tallow alcohol, 7 parts sodiumtripolyphosphate, 1.0 part sodium dodecyl benzene sulfonate and 1.0 partsodium tallow alkyl sulfate.

100 parts of the spray-dried detergent granules are mixed with 11.2parts of the enzyme-carrier composition and 10 parts anhydrous trisodiumphosphate. The combination of trisodium phosphate and solubilizedprotein (WSP-X-l000) has a definite stabilizing effect on enzymes inthis granular detergent composition.

Example V Results substantially similar to those in the previousexamples are obtained when the following enzymes or commercial enzymecompositions are substituted for Alcalase on an equal weight of enzymebasis: Wallerstein bacterial a-amylase, lot number 4546A; Milestat-amylase; pepsin; trypsin; chymotrypsin; collagenase; keratinase;elastase; subtilisin; BPN'; papain; iicin; bromelin; carboxy peptidase;amino peptidase; aspergillopeptidase A; aspergillopeptidase B;proteolytic enzymes derived from Streptomyces species; Maxatase;Protease B4000; Sandoz AP 2100; CRD-Protease; Pronase-E; Pronase-P;Pronase- AF; Biophrase; Rapidase 400; Rhozyme PF, proteolytic enzyme 7XBand Wallerstein 627-P.

Results substantially similar to those in the previous examples areobtained in that the enzymes are stabilized when 10 parts anhydroustrisodium phosphate are used in combination with Composition A ofExample I, when 10 parts of sodium perborate trihydrate are used incombination with Composition D of Example II, and when 10 parts ofanhydrous trisodium phosphate are used in combination with Composition Gof Example III.

Results substantially similar to those in the previous examples areobtained in that the enzymes are stabilized when anhydrous calciumsulfate is substituted for anhydrous trisodium phosphate.

Results substantially similar to those in the previous examples areobtained in that the enzymes are stabilized when the following proteinsare substituted on an equal weight basis for WSP-X1000 and casein: Knoxgelatin, alpha protein, zein collagen, bovine albumin and egg albumin.

Results substantially similar to those obtained in the previous examplesare obtained when the following polymeric builder salts are substitutedeither wholly or in part for sodium tripolyphosphate in that the enzymesare stabilized: sodium, potassium, ammonium, monoethanol ammonium,diethanol ammonium and triethanol ammonium salts of the following acids:ethylene diaminetetraacetic acid;N-(2-hydroxyethyl)-ethylenediaminetriacetic acid; N-(2-hydroxyethyl)-nitrolodiacetic acid; diethylenetriaminepentaaceticacid; nitrilotriacetic acid; ethylene diphosphonic acid; ethane 1hydroxy 1,1- diphosphonic acid; ethane 1 hydroxy 1,1 diphosphonic acid;ethane 1,1,2-triphosphonic acid; ethane-2- carboxy 1,1 diphosphonicacid, hydroxymethane-diphosphonic acid, carbonyldiphosphonic acid;ethane 1- hydroxy 1,1,2 triphosphonic acid; ethane-2-hydroxy-1,1,2-triphosphonic acid, propane 1,1,3,3-tetraphos phonic acid; propanel,1,2,3 tetraphosphonic acid; and propane i1,2,2,3-tetraphosphonic acidand potassium tripolyphosphate; and salts of polymers of itaconic acid,aconitic acid, maleic acid, mesaconic acid, fumaric acid, methylenemalonic acid and citraconic acid and copolymers with themselves and/orethylene and/oracrylic acid in, e.g., 1:1 molar ratios and havingmolecular weights of 75,000; 100,000; and 125,000 (the copolymers withethylene and/or acrylic acid having equivalent weights, based on theacid form of 65, 70 and 75); in the form of their sodium, potassium,triethanolammonium, diethanolammonium and monoethanolammonium salts.

Results substantially similar to those obtained in the previous examplesare obtained when the following organic detergents are substituted,either wholly or in part, for sodium alkyl benzene sulfonate derivedfrom tetrapropylene and sodium tallow alkyl sulfate in that the enzymesare stabilized: sodium linear dodecyl benzene sulfonate, thecondensation product of 1 mole of dodecyl phenol with 15 moles ofethylene oxide, dimethyldodecylamine oxide, dimethyldodecylphosphineoxide, 3 (N,N- dimethyl N -.hexadecylammonio) 2 hydroxypropane- 1sulfonate and sodium 3 dodecylaminopropane sulfonate.

Results substantially similar to those obtained in the previous examplesare obtained when the following protective packages are substituted forglass jars and polyethylene bags in that the enzymes are stabilized:foil wrapped cartons, asphalt laminated cartons and outer wax laminatedcartons.

What is claimed is:

1. A granular, enzyme-containing detergent composition consistingessentially of, by weight of the detergent composition;

a (1) from about 60% to about 98% of detergent granules comprisingpolymeric builder salts and organic detergents, the ratio of polymericbuilder salts to organic detergents in the detergent composition of thisinvention ranging from about 30:1 to about 1:4;

said organic detergents being selected from the group consisting ofsoaps, anionic synthetic detergents,

nonionic synthetic detergents, zwitterionic synthetic detergents;ampholytic synthetic detergents, and mixtures thereof;

(2) from about 0.001% to about 1.0% of proteases which are active in thepH range of from about 5.0 to about 11.0 and in the temperature range offrom about 50 F. to about 170 F.; and

(3) a mixture of environmental control components consisting essentiallyof proteins in an effective amount to stabilize the enzymes in thegranular detergent, said proteins having a molecular weight of betweenabout 5,000 and 1,000,000 and being soluble or dispersible in water; andcomponents selected from the group consisting of from about 5% to about30% of sodium perborate trihydrate; from about 4% to about 15% ofcompounds which hydrate at below about 50% relative humidity andselected from anhydrous trisodium phosphate, anhydrouscalcium sulfateand mixtures thereof; and mixtures of from about 5% to about 30% ofsodium perborate trihydrate and from about 4% to about 15% of saidcompounds which hydrate below about 50% relative humidity.

2. The granular, enzyme-containing detergent composition of claim 1wherein:

(1) the detergent granules are present in an amount of from 70% to 95%;and

(2) the enzymes are present in an amount of from about 0.01% to about0.5%.

3. The granular, enzyme-containing detergent composition of claim 1wherein the polymeric builder salts are selected from the groupconsisting of polyphosphate, 5 polyphosphonate, polyacetate andpolycarboxylate builder salts and mixtures thereof.

4. The granular, enzyme-containing detergent composition of claim 1wherein the moisture content of the detergent granules is not more than8% by weight of the detergent granules.

5. The granular, enzyme-containing detergent composition of claim 1wherein the enzymes are proteases and are selected from the groupconsisting of subtilisin, BPN', and those proteases isolated fromStreptomyces species.

6. The granular, enzyme-containing detergent composi tion of claim 1wherein the components which hydrate at relative humidities of less than50% comprise from about 7% to about 15% of the detergent composition.

7. The granular, enzyme-containing detergent composition of claim 6wherein the component which hydrates at relative humidities of less than50% is anhydrous trisodium phosphate.

8. The granular, enzyme-containing detergent com- 55 position of claim 1wherein the protein is utilized in a weight ratio of protein to enzymesof from about 1:1 to about 10:1.

References Cited UNITED .STATES PATENTS 282,588 12/1927 Great Britain252-89 LEON D. ROSDOL, Primary Examiner W. E. SCHULZ, Assistant ExaminerUS. Cl. X.R.

g3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION patent3,558,498 Dated January 26, 1971 Inventor) Jean-Pierre D. B. Eymery andHarold H. Beyer It is cettified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 4, line 53, after the word "herein" in was omitted.

Column 5, line 49, the word "if" should read of Column 6, lines 1 and 2,after the word "some" the following was omitted a-amylase; Rapidase 400;HT proteoly enzyme 200 Signed and sealed this 19th day of October 1971(SEAL) Attest:

EDWARD M.FLEICHER,JR. ROBERT GOTTSCHALK Attesting Officer ActingCommissioner of Patents

